Acetylcholine is a neurotransmitter that induces signal transduction in the central nervous system and the neuromuscular connections (the parasympathetic nerve and motor nerve). In the central nervous system, nuclei of origin of the acetylcholine neuron are in the brain stem and forebrain, and those acetylcholine neurons project to cerebral cortex, hippocampus, and limbic area. In addition, some interneurons in some brain areas such as striatum utilize acetylcholine as a neurotransmitter. Acetylcholine receptor is classified into a ligand dependent ion channel (cholinergic nicotinic receptor) and a G-protein-conjugated receptor (cholinergic muscarinic receptor). The cholinergic muscarinic receptor is one kind of receptor for excitatory neurotransmitter acetylcholine, and was named based on the selective activation of the receptor by muscarine. The muscarinic receptor is further classified into subtypes of M1 to M5, and the M1 receptor is known to be widely distributed mainly in the brain, and deeply involved particularly in learning, memory, sleep, neuropathic pain and the like. The importance of cholinergic muscarinic M1 receptor in brain physiology is well known, and a compound having an M1 receptor function enhancing action is expected to be useful as a prophylactic or therapeutic drug for mental diseases, neurodegenerative diseases, memory disorders, pain, sleep disorders and the like (non-patent document 1).
WO 2011/117254 A1 (patent document 1) discloses the following compound as a modulator of ghrelin receptor.
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US 2008/0269234 A1 (patent document 2) discloses the following compound as a poly(ADP-ribose)polymerase inhibitor.
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WO 2010/025179 A1 (patent document 3) discloses the following compound as a liver X receptor (LXRα and LxRβ) modulator.
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WO 2012/003544 A1 (patent document 4) discloses the following compound as a protein kinase inhibitor.
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WO 2010/054764 A1 (patent document 5) discloses the following compound as a HIF inhibitor.
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WO 2013/129622 A1 (patent document 6) discloses the following compound as a compound having an M1PAM activity, and effective for Alzheimer's disease and the like.
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WO 2014/077401 A1 (patent document 7) discloses the following compound having a cholinergic muscarinic M1 receptor positive allosteric modulator activity and useful as a prophylactic or therapeutic drug for Alzheimer's disease, schizophrenia, pain, sleep disorder and the like.
wherein each symbol is as defined in the document.